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ONP - Oxidation State

ONP

Refers to Old Newspapers for recycling.

Orbital

the area around an atom where according to orbital theory the probability of finding an electron is the greatest. More Information

Orbital Theory

the quantum theory matter that combines Schrodinger's wave mechanics and Heisenburg's uncertainty principle and applies this to the behavior and nature of electrons. Orbital theory was formulated in 1926 and has yielded a better understanding of electrons and their critical role in chemical bonding than is possible with Newtonian mechanics.

OSHA

United States Occupational Safety and Health Administration. This federal agency is responsible for writing and enforcing federal regulations related to workplace safety (Code of Federal Regulations Title 29).

Oxidation State (Oxidation Number)

Either the actual charge of an atom (ion) in a substance, assuming the atom exists as a monatomic ion, or a hypothetical charge assigned by simple rules. 2) The charge an atom would have in a substance if the pairs of electrons in each bond belonged to the more electronegative atom. 3) The number of electrons that must be added or subtracted from an atom in a combined state to convert it to the elemental form.

Generally the following rules for assigning oxidation numbers to an atom can be used:

  1. In its elementary state the oxidation number of an atom is zero. For instance the oxidation number for chlorine Cl2 or oxygen O2 is zero.
  2. All Group IA (alkali metals) elements have an oxidation number of +1 in any compound. All Group IIA (alkali earth metals) elements have an oxidation number of +2 in any compound.
  3. Fluorine has an oxidation number of -1 in all of its compounds.
  4. Chlorine, bromine and iodine have an oxidation number of -1 in any compound of halogen with a less electronegative element.
  5. Usually oxygen has an oxidation number of -2 in a compound. Peroxides, like H2O2 and Na2O2, are the major exceptions to this and in these cases oxygen has an oxidation number of -1.
  6. Hydrogen has an oxidation number of +1 in most of its compounds. In hydrides (compounds like NaH), however, in which hydrogen is bonded to metallic elements, hydrogen has an oxidation number of -1.
  7. The sum of the oxidation numbers of the atoms in a compound always equals zero. For polyatomic ions, the oxidation numbers of the atoms add up to the charge of the ion.

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